Petroleum: Drilling Contractors (OG-06) About 98 percent of all
drilling in the United States is done by the drilling contractor, whose
main job is to drill the hole to the depth and specifications of the
operating company. Because drilling is usually secured by bids, the
contractor must be competitive in prices and services to stay in business.
Because drilling requires large quantities of expendable supplies, such as
casing, bits and drilling mud, the operator and the contractor buy these
materials from companies that specialize in particular services. Numerous
service and supply companies work at large drill sites at one time or
another. Coordinating these services are the managers and engineers of the
operating company, who work as a team with the drilling contractor.